From 4470fe715c359f953dd07951f1732d5a209d1c59 Mon Sep 17 00:00:00 2001
From: Russell Harmon <eatnumber1@google.com>
Date: Sat, 18 Jun 2016 22:15:01 -0700
Subject: [PATCH 01/12] Support emitting a correct end column on SC2086

This does the necessary work to emit end columns on AST analyses. SC2086
is made to emit a correct end column as an illustrative example.

For example:
```
$ shellcheck -s bash -f json /dev/stdin <<< 'echo $1'
[{"file":"/dev/stdin","line":1,"endLine":1,"column":6,"endColumn":8,"level":"info","code":2086,"message":"Double quote to prevent globbing and word splitting."}]
```

This change deprecates the parser's getNextId and getNextIdAt, replacing
it with a new withNextId function. This function has the type signature:

withNextId :: Monad m => ParsecT s UserState (SCBase m) (Id -> b) -> ParsecT s UserState (SCBase m) b

Specifically, it should be used to wrap read* functions and will pass in
a newly generated Id which should be used to represent that node.
Sub-parsers will need their own call to withNextId in order to get a
unique Id.

In doing this, withNextId can now track both the entry and exit position
of every read* parser which uses it, enabling the tracking of end
columns throughout the application.
---
 src/ShellCheck/Checker.hs   | 12 ++++---
 src/ShellCheck/Interface.hs |  1 +
 src/ShellCheck/Parser.hs    | 63 +++++++++++++++++++++++++++++--------
 3 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/src/ShellCheck/Checker.hs b/src/ShellCheck/Checker.hs
index 72259ad..3127c26 100644
--- a/src/ShellCheck/Checker.hs
+++ b/src/ShellCheck/Checker.hs
@@ -29,6 +29,7 @@ import Data.Functor
 import Data.List
 import Data.Maybe
 import Data.Ord
+import Control.Applicative
 import Control.Monad.Identity
 import qualified Data.Map as Map
 import qualified System.IO
@@ -37,11 +38,14 @@ import Control.Monad
 
 import Test.QuickCheck.All
 
-tokenToPosition map (TokenComment id c) = fromMaybe fail $ do
-    position <- Map.lookup id map
-    return $ PositionedComment position position c
+tokenToPosition startMap endMap (TokenComment id c) = fromMaybe fail $ do
+    position <- maybePosition
+    endPosition <- maybeEndPosition <|> maybePosition
+    return $ PositionedComment position endPosition c
   where
     fail = error "Internal shellcheck error: id doesn't exist. Please report!"
+    maybeEndPosition = Map.lookup id endMap
+    maybePosition = Map.lookup id startMap
 
 checkScript :: Monad m => SystemInterface m -> CheckSpec -> m CheckResult
 checkScript sys spec = do
@@ -62,7 +66,7 @@ checkScript sys spec = do
                 fromMaybe [] $
                     (arComments . analyzeScript . analysisSpec)
                         <$> prRoot result
-        let translator = tokenToPosition (prTokenPositions result)
+        let translator = tokenToPosition (prTokenPositions result) (prTokenEndPositions result)
         return . nub . sortMessages . filter shouldInclude $
             (parseMessages ++ map translator analysisMessages)
 
diff --git a/src/ShellCheck/Interface.hs b/src/ShellCheck/Interface.hs
index a76c7e0..001222d 100644
--- a/src/ShellCheck/Interface.hs
+++ b/src/ShellCheck/Interface.hs
@@ -62,6 +62,7 @@ data ParseSpec = ParseSpec {
 data ParseResult = ParseResult {
     prComments :: [PositionedComment],
     prTokenPositions :: Map.Map Id Position,
+    prTokenEndPositions :: Map.Map Id Position,
     prRoot :: Maybe Token
 } deriving (Show, Eq)
 
diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index dafbe0a..5adae09 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -136,6 +136,38 @@ almostSpace =
         char c
         return ' '
 
+withNextId :: Monad m => ParsecT s UserState (SCBase m) (Id -> b) -> ParsecT s UserState (SCBase m) b
+withNextId p = do
+    start <- getPosition
+    id <- createId
+    setStartPos id start
+    fn <- p
+    let t = fn id
+    end <- getPosition
+    setEndPos id end
+    return t
+  where
+    createId = do
+        state <- getState
+        let id = incId (lastId state)
+        putState $ state {
+            lastId = id
+        }
+        return id
+      where incId (Id n) = Id $ n+1
+    setStartPos id sourcepos = do
+      state <- getState
+      let newMap = Map.insert id sourcepos (positionMap state)
+      putState $ state {
+          positionMap = newMap
+      }
+    setEndPos id sourcepos = do
+      state <- getState
+      let newMap = Map.insert id sourcepos (positionEndMap state)
+      putState $ state {
+          positionEndMap = newMap
+      }
+
 --------- Message/position annotation on top of user state
 data Note = Note Id Severity Code String deriving (Show, Eq)
 data ParseNote = ParseNote SourcePos SourcePos Severity Code String deriving (Show, Eq)
@@ -152,6 +184,7 @@ data HereDocContext =
 data UserState = UserState {
     lastId :: Id,
     positionMap :: Map.Map Id SourcePos,
+    positionEndMap :: Map.Map Id SourcePos,
     parseNotes :: [ParseNote],
     hereDocMap :: Map.Map Id [Token],
     pendingHereDocs :: [HereDocContext]
@@ -159,6 +192,7 @@ data UserState = UserState {
 initialUserState = UserState {
     lastId = Id $ -1,
     positionMap = Map.empty,
+    positionEndMap = Map.empty,
     parseNotes = [],
     hereDocMap = Map.empty,
     pendingHereDocs = []
@@ -172,6 +206,7 @@ noteToParseNote map (Note id severity code message) =
 
 getLastId = lastId <$> getState
 
+-- Deprecated by withNextId
 getNextIdAt sourcepos = do
     state <- getState
     let newId = incId (lastId state)
@@ -183,6 +218,7 @@ getNextIdAt sourcepos = do
     return newId
   where incId (Id n) = Id $ n+1
 
+-- Deprecated by withNextId
 getNextId :: Monad m => SCParser m Id
 getNextId = do
     pos <- getPosition
@@ -1190,8 +1226,7 @@ prop_readDoubleQuoted7 = isOk readSimpleCommand "echo \"${ ls;}bar\""
 prop_readDoubleQuoted8 = isWarning readDoubleQuoted "\"\x201Chello\x201D\""
 prop_readDoubleQuoted9 = isWarning readDoubleQuoted "\"foo\\n\""
 prop_readDoubleQuoted10 = isOk readDoubleQuoted "\"foo\\\\n\""
-readDoubleQuoted = called "double quoted string" $ do
-    id <- getNextId
+readDoubleQuoted = called "double quoted string" $ withNextId $ do
     startPos <- getPosition
     doubleQuote
     x <- many doubleQuotedPart
@@ -1201,7 +1236,7 @@ readDoubleQuoted = called "double quoted string" $ do
         try . lookAhead $ suspectCharAfterQuotes <|> oneOf "$\""
         when (any hasLineFeed x && not (startsWithLineFeed x)) $
             suggestForgotClosingQuote startPos endPos "double quoted string"
-    return $ T_DoubleQuoted id x
+    return $ \id -> T_DoubleQuoted id x
   where
     startsWithLineFeed (T_Literal _ ('\n':_):_) = True
     startsWithLineFeed _ = False
@@ -1544,16 +1579,18 @@ prop_readDollarVariable3 = isWarning (readDollarVariable >> anyChar) "$10"
 prop_readDollarVariable4 = isWarning (readDollarVariable >> string "[@]") "$arr[@]"
 prop_readDollarVariable5 = isWarning (readDollarVariable >> string "[f") "$arr[f"
 
-readDollarVariable = do
-    id <- getNextId
+readDollarVariable :: Monad m => ParsecT String UserState (SCBase m) Token
+readDollarVariable = withNextId $ do
     pos <- getPosition
 
-    let singleCharred p = do
+    let
+      singleCharred p = do
         n <- p
         value <- wrap [n]
-        return (T_DollarBraced id value)
+        return $ \id -> (T_DollarBraced id value)
 
-    let positional = do
+    let
+      positional = do
         value <- singleCharred digit
         return value `attempting` do
             lookAhead digit
@@ -1564,17 +1601,15 @@ readDollarVariable = do
     let regular = do
         name <- readVariableName
         value <- wrap name
-        return (T_DollarBraced id value) `attempting` do
+        return (\id -> (T_DollarBraced id value)) `attempting` do
             lookAhead $ char '['
             parseNoteAt pos ErrorC 1087 "Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet)."
 
     try $ char '$' >> (positional <|> special <|> regular)
 
   where
-    wrap s = do
-        x <- getNextId
-        y <- getNextId
-        return $ T_NormalWord x [T_Literal y s]
+    wrap s = withNextId $ withNextId $ do
+        return $ \x y -> T_NormalWord x [T_Literal y s]
 
 readVariableName = do
     f <- variableStart
@@ -3002,6 +3037,7 @@ parseShell env name contents = do
             return ParseResult {
                 prComments = map toPositionedComment $ nub $ parseNotes userstate ++ parseProblems state,
                 prTokenPositions = Map.map posToPos (positionMap userstate),
+                prTokenEndPositions = Map.map posToPos (positionEndMap userstate),
                 prRoot = Just $
                     reattachHereDocs script (hereDocMap userstate)
             }
@@ -3013,6 +3049,7 @@ parseShell env name contents = do
                         ++ [makeErrorFor err]
                         ++ parseProblems state,
                 prTokenPositions = Map.empty,
+                prTokenEndPositions = Map.empty,
                 prRoot = Nothing
             }
 

From 48ac654a9369b029f234c510c0347507d75ef524 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Sat, 26 May 2018 23:25:22 -0700
Subject: [PATCH 02/12] Merge end pos map into start pos map

---
 src/ShellCheck/Checker.hs   |  8 +++----
 src/ShellCheck/Interface.hs |  3 +--
 src/ShellCheck/Parser.hs    | 48 ++++++++++++++++---------------------
 3 files changed, 26 insertions(+), 33 deletions(-)

diff --git a/src/ShellCheck/Checker.hs b/src/ShellCheck/Checker.hs
index 3127c26..4b0ba1e 100644
--- a/src/ShellCheck/Checker.hs
+++ b/src/ShellCheck/Checker.hs
@@ -38,14 +38,14 @@ import Control.Monad
 
 import Test.QuickCheck.All
 
-tokenToPosition startMap endMap (TokenComment id c) = fromMaybe fail $ do
+tokenToPosition startMap (TokenComment id c) = fromMaybe fail $ do
     position <- maybePosition
     endPosition <- maybeEndPosition <|> maybePosition
     return $ PositionedComment position endPosition c
   where
     fail = error "Internal shellcheck error: id doesn't exist. Please report!"
-    maybeEndPosition = Map.lookup id endMap
-    maybePosition = Map.lookup id startMap
+    maybePosition = fmap fst $ Map.lookup id startMap
+    maybeEndPosition = join $ fmap snd $ Map.lookup id startMap
 
 checkScript :: Monad m => SystemInterface m -> CheckSpec -> m CheckResult
 checkScript sys spec = do
@@ -66,7 +66,7 @@ checkScript sys spec = do
                 fromMaybe [] $
                     (arComments . analyzeScript . analysisSpec)
                         <$> prRoot result
-        let translator = tokenToPosition (prTokenPositions result) (prTokenEndPositions result)
+        let translator = tokenToPosition (prTokenPositions result)
         return . nub . sortMessages . filter shouldInclude $
             (parseMessages ++ map translator analysisMessages)
 
diff --git a/src/ShellCheck/Interface.hs b/src/ShellCheck/Interface.hs
index 001222d..fb5f492 100644
--- a/src/ShellCheck/Interface.hs
+++ b/src/ShellCheck/Interface.hs
@@ -61,8 +61,7 @@ data ParseSpec = ParseSpec {
 
 data ParseResult = ParseResult {
     prComments :: [PositionedComment],
-    prTokenPositions :: Map.Map Id Position,
-    prTokenEndPositions :: Map.Map Id Position,
+    prTokenPositions :: Map.Map Id (Position, Maybe Position),
     prRoot :: Maybe Token
 } deriving (Show, Eq)
 
diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 5adae09..59d67dc 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -136,15 +136,14 @@ almostSpace =
         char c
         return ' '
 
-withNextId :: Monad m => ParsecT s UserState (SCBase m) (Id -> b) -> ParsecT s UserState (SCBase m) b
+withNextId :: Monad m => SCParser m (Id -> b) -> SCParser m b
 withNextId p = do
     start <- getPosition
     id <- createId
-    setStartPos id start
     fn <- p
     let t = fn id
     end <- getPosition
-    setEndPos id end
+    setPos id start end
     return t
   where
     createId = do
@@ -155,18 +154,12 @@ withNextId p = do
         }
         return id
       where incId (Id n) = Id $ n+1
-    setStartPos id sourcepos = do
+    setPos id start end = do
       state <- getState
-      let newMap = Map.insert id sourcepos (positionMap state)
+      let newMap = Map.insert id (start, Just end) (positionMap state)
       putState $ state {
           positionMap = newMap
       }
-    setEndPos id sourcepos = do
-      state <- getState
-      let newMap = Map.insert id sourcepos (positionEndMap state)
-      putState $ state {
-          positionEndMap = newMap
-      }
 
 --------- Message/position annotation on top of user state
 data Note = Note Id Severity Code String deriving (Show, Eq)
@@ -183,8 +176,7 @@ data HereDocContext =
 
 data UserState = UserState {
     lastId :: Id,
-    positionMap :: Map.Map Id SourcePos,
-    positionEndMap :: Map.Map Id SourcePos,
+    positionMap :: Map.Map Id (SourcePos, Maybe SourcePos),
     parseNotes :: [ParseNote],
     hereDocMap :: Map.Map Id [Token],
     pendingHereDocs :: [HereDocContext]
@@ -192,7 +184,6 @@ data UserState = UserState {
 initialUserState = UserState {
     lastId = Id $ -1,
     positionMap = Map.empty,
-    positionEndMap = Map.empty,
     parseNotes = [],
     hereDocMap = Map.empty,
     pendingHereDocs = []
@@ -210,7 +201,7 @@ getLastId = lastId <$> getState
 getNextIdAt sourcepos = do
     state <- getState
     let newId = incId (lastId state)
-    let newMap = Map.insert newId sourcepos (positionMap state)
+    let newMap = Map.insert newId (sourcepos, Just sourcepos) (positionMap state)
     putState $ state {
         lastId = newId,
         positionMap = newMap
@@ -354,7 +345,7 @@ parseProblemAt pos = parseProblemAtWithEnd pos pos
 parseProblemAtId :: Monad m => Id -> Severity -> Integer -> String -> SCParser m ()
 parseProblemAtId id level code msg = do
     map <- getMap
-    let pos = Map.findWithDefault
+    let (pos, _) = Map.findWithDefault
                 (error "Internal error (no position for id). Please report.") id map
     parseProblemAt pos level code msg
 
@@ -1579,18 +1570,16 @@ prop_readDollarVariable3 = isWarning (readDollarVariable >> anyChar) "$10"
 prop_readDollarVariable4 = isWarning (readDollarVariable >> string "[@]") "$arr[@]"
 prop_readDollarVariable5 = isWarning (readDollarVariable >> string "[f") "$arr[f"
 
-readDollarVariable :: Monad m => ParsecT String UserState (SCBase m) Token
+readDollarVariable :: Monad m => SCParser m Token
 readDollarVariable = withNextId $ do
     pos <- getPosition
 
-    let
-      singleCharred p = do
+    let singleCharred p = do
         n <- p
         value <- wrap [n]
         return $ \id -> (T_DollarBraced id value)
 
-    let
-      positional = do
+    let positional = do
         value <- singleCharred digit
         return value `attempting` do
             lookAhead digit
@@ -1679,7 +1668,7 @@ readPendingHereDocs = do
       swapContext ctx $
       do
         docPos <- getPosition
-        tokenPos <- Map.findWithDefault (error "Missing ID") id <$> getMap
+        (tokenPos, _) <- Map.findWithDefault (error "Missing ID") id <$> getMap
         (terminated, wasWarned, lines) <- readDocLines dashed endToken
         let hereData = unlines lines
         unless terminated $ do
@@ -2945,11 +2934,15 @@ debugParseScript string =
     result {
         -- Remove the noisiest parts
         prTokenPositions = Map.fromList [
-            (Id 0, Position {
+            (Id 0, (Position {
                 posFile = "removed for clarity",
                 posLine = -1,
                 posColumn = -1
-            })]
+            }, Just Position {
+                posFile = "removed for clarity",
+                posLine = -1,
+                posColumn = -1
+            }))]
     }
   where
     result = runIdentity $
@@ -3036,8 +3029,7 @@ parseShell env name contents = do
         Right (script, userstate) ->
             return ParseResult {
                 prComments = map toPositionedComment $ nub $ parseNotes userstate ++ parseProblems state,
-                prTokenPositions = Map.map posToPos (positionMap userstate),
-                prTokenEndPositions = Map.map posToPos (positionEndMap userstate),
+                prTokenPositions = Map.map startEndPosToPos (positionMap userstate),
                 prRoot = Just $
                     reattachHereDocs script (hereDocMap userstate)
             }
@@ -3049,7 +3041,6 @@ parseShell env name contents = do
                         ++ [makeErrorFor err]
                         ++ parseProblems state,
                 prTokenPositions = Map.empty,
-                prTokenEndPositions = Map.empty,
                 prRoot = Nothing
             }
 
@@ -3119,6 +3110,9 @@ posToPos sp = Position {
     posColumn = fromIntegral $ sourceColumn sp
 }
 
+startEndPosToPos :: (SourcePos, Maybe SourcePos) -> (Position, Maybe Position)
+startEndPosToPos (s, me) = (posToPos s, fmap posToPos me)
+
 -- TODO: Clean up crusty old code that this is layered on top of
 parseScript :: Monad m =>
         SystemInterface m -> ParseSpec -> m ParseResult

From e496b413bdbd9b3bf5377bf03385fa57432db171 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Thu, 7 Jun 2018 21:30:20 -0700
Subject: [PATCH 03/12] Remove usage of withNextId

---
 src/ShellCheck/Parser.hs | 45 ++++++++++------------------------------
 1 file changed, 11 insertions(+), 34 deletions(-)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 59d67dc..c7224f4 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -136,31 +136,6 @@ almostSpace =
         char c
         return ' '
 
-withNextId :: Monad m => SCParser m (Id -> b) -> SCParser m b
-withNextId p = do
-    start <- getPosition
-    id <- createId
-    fn <- p
-    let t = fn id
-    end <- getPosition
-    setPos id start end
-    return t
-  where
-    createId = do
-        state <- getState
-        let id = incId (lastId state)
-        putState $ state {
-            lastId = id
-        }
-        return id
-      where incId (Id n) = Id $ n+1
-    setPos id start end = do
-      state <- getState
-      let newMap = Map.insert id (start, Just end) (positionMap state)
-      putState $ state {
-          positionMap = newMap
-      }
-
 --------- Message/position annotation on top of user state
 data Note = Note Id Severity Code String deriving (Show, Eq)
 data ParseNote = ParseNote SourcePos SourcePos Severity Code String deriving (Show, Eq)
@@ -197,7 +172,6 @@ noteToParseNote map (Note id severity code message) =
 
 getLastId = lastId <$> getState
 
--- Deprecated by withNextId
 getNextIdAt sourcepos = do
     state <- getState
     let newId = incId (lastId state)
@@ -209,7 +183,6 @@ getNextIdAt sourcepos = do
     return newId
   where incId (Id n) = Id $ n+1
 
--- Deprecated by withNextId
 getNextId :: Monad m => SCParser m Id
 getNextId = do
     pos <- getPosition
@@ -1217,7 +1190,8 @@ prop_readDoubleQuoted7 = isOk readSimpleCommand "echo \"${ ls;}bar\""
 prop_readDoubleQuoted8 = isWarning readDoubleQuoted "\"\x201Chello\x201D\""
 prop_readDoubleQuoted9 = isWarning readDoubleQuoted "\"foo\\n\""
 prop_readDoubleQuoted10 = isOk readDoubleQuoted "\"foo\\\\n\""
-readDoubleQuoted = called "double quoted string" $ withNextId $ do
+readDoubleQuoted = called "double quoted string" $ do
+    id <- getNextId
     startPos <- getPosition
     doubleQuote
     x <- many doubleQuotedPart
@@ -1227,7 +1201,7 @@ readDoubleQuoted = called "double quoted string" $ withNextId $ do
         try . lookAhead $ suspectCharAfterQuotes <|> oneOf "$\""
         when (any hasLineFeed x && not (startsWithLineFeed x)) $
             suggestForgotClosingQuote startPos endPos "double quoted string"
-    return $ \id -> T_DoubleQuoted id x
+    return $ T_DoubleQuoted id x
   where
     startsWithLineFeed (T_Literal _ ('\n':_):_) = True
     startsWithLineFeed _ = False
@@ -1571,13 +1545,14 @@ prop_readDollarVariable4 = isWarning (readDollarVariable >> string "[@]") "$arr[
 prop_readDollarVariable5 = isWarning (readDollarVariable >> string "[f") "$arr[f"
 
 readDollarVariable :: Monad m => SCParser m Token
-readDollarVariable = withNextId $ do
+readDollarVariable = do
+    id <- getNextId
     pos <- getPosition
 
     let singleCharred p = do
         n <- p
         value <- wrap [n]
-        return $ \id -> (T_DollarBraced id value)
+        return $ (T_DollarBraced id value)
 
     let positional = do
         value <- singleCharred digit
@@ -1590,15 +1565,17 @@ readDollarVariable = withNextId $ do
     let regular = do
         name <- readVariableName
         value <- wrap name
-        return (\id -> (T_DollarBraced id value)) `attempting` do
+        return (T_DollarBraced id value) `attempting` do
             lookAhead $ char '['
             parseNoteAt pos ErrorC 1087 "Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet)."
 
     try $ char '$' >> (positional <|> special <|> regular)
 
   where
-    wrap s = withNextId $ withNextId $ do
-        return $ \x y -> T_NormalWord x [T_Literal y s]
+    wrap s = do
+        x <- getNextId
+        y <- getNextId
+        return $ T_NormalWord x [T_Literal y s]
 
 readVariableName = do
     f <- variableStart

From 0c459ae2cb42be1d5bd8b8f883e04a75dbd5e9ce Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Thu, 7 Jun 2018 21:32:49 -0700
Subject: [PATCH 04/12] Add function to set end pos of start id

---
 src/ShellCheck/Parser.hs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index c7224f4..a11af7a 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -188,6 +188,16 @@ getNextId = do
     pos <- getPosition
     getNextIdAt pos
 
+endPosOfStartId s = do
+    endPos <- getPosition
+    state <- getState
+    let setEndPos (start, _) = Just (start, Just endPos)
+    let newMap = Map.update setEndPos s (positionMap state)
+    putState $ state {
+        lastId = s,
+        positionMap = newMap
+    }
+
 addToHereDocMap id list = do
     state <- getState
     let map = hereDocMap state

From 3848788c2d277b1fc24b39fab0551f038d234976 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Thu, 7 Jun 2018 21:52:29 -0700
Subject: [PATCH 05/12] Add end pos to readDollarVariable

---
 src/ShellCheck/Parser.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index a11af7a..2d5290b 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -1562,6 +1562,7 @@ readDollarVariable = do
     let singleCharred p = do
         n <- p
         value <- wrap [n]
+        endPosOfStartId id
         return $ (T_DollarBraced id value)
 
     let positional = do
@@ -1575,6 +1576,7 @@ readDollarVariable = do
     let regular = do
         name <- readVariableName
         value <- wrap name
+        endPosOfStartId id
         return (T_DollarBraced id value) `attempting` do
             lookAhead $ char '['
             parseNoteAt pos ErrorC 1087 "Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet)."

From 29e8c0a16ecbef90171936998d064880ac66e194 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Thu, 7 Jun 2018 22:25:09 -0700
Subject: [PATCH 06/12] Add end pos to readDollarBraced

---
 src/ShellCheck/Parser.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 2d5290b..0488b00 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -1536,6 +1536,7 @@ readDollarBraced = called "parameter expansion" $ do
     try (string "${")
     word <- readDollarBracedWord
     char '}'
+    endPosOfStartId id
     return $ T_DollarBraced id word
 
 prop_readDollarExpansion1= isOk readDollarExpansion "$(echo foo; ls\n)"

From 8ff35fb4af895353ed035be8304beca067a9b2af Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Thu, 7 Jun 2018 23:09:59 -0700
Subject: [PATCH 07/12] Add end pos to readSingleQuoted

---
 src/ShellCheck/Parser.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 0488b00..a608403 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -1097,6 +1097,7 @@ readSingleQuoted = called "single quoted string" $ do
             when ('\n' `elem` string && not ("\n" `isPrefixOf` string)) $
                 suggestForgotClosingQuote startPos endPos "single quoted string"
 
+    endPosOfStartId id
     return (T_SingleQuoted id string)
 
 readSingleQuotedLiteral = do

From 1699c9e9ba597dacd405c9bef5768fad35f12344 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Tue, 12 Jun 2018 21:56:53 -0700
Subject: [PATCH 08/12] Add api to begin and end a span of source code

---
 src/ShellCheck/Parser.hs | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index a608403..3cb2411 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -188,6 +188,27 @@ getNextId = do
     pos <- getPosition
     getNextIdAt pos
 
+data IncompleteInterval = IncompleteInterval SourcePos
+
+startSpan = IncompleteInterval <$> getPosition
+
+endSpan (IncompleteInterval start) = do
+    id <- getNextIdAt start
+    endPos <- getPosition
+    state <- getState
+    let setEndPos (start, _) = Just (start, Just endPos)
+    let newMap = Map.update setEndPos id (positionMap state)
+    putState $ state {
+        lastId = id,
+        positionMap = newMap
+    }
+    return id
+
+zeroWidthSpan = do
+    start <- startSpan
+    id <- endSpan start
+    return id
+
 endPosOfStartId s = do
     endPos <- getPosition
     state <- getState

From e717802de1ddf66bbe1f91feddd26d132f2fc726 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Tue, 12 Jun 2018 22:11:11 -0700
Subject: [PATCH 09/12] Change usage of endPosOfStartId to startSpan and
 endSpan

---
 src/ShellCheck/Parser.hs | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 3cb2411..8daa957 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -209,16 +209,6 @@ zeroWidthSpan = do
     id <- endSpan start
     return id
 
-endPosOfStartId s = do
-    endPos <- getPosition
-    state <- getState
-    let setEndPos (start, _) = Just (start, Just endPos)
-    let newMap = Map.update setEndPos s (positionMap state)
-    putState $ state {
-        lastId = s,
-        positionMap = newMap
-    }
-
 addToHereDocMap id list = do
     state <- getState
     let map = hereDocMap state
@@ -1100,7 +1090,7 @@ prop_readSingleQuoted6 = isOk readSimpleCommand "foo='bar cow 'arg"
 prop_readSingleQuoted7 = isOk readSingleQuoted "'foo\x201C\&bar'"
 prop_readSingleQuoted8 = isWarning readSingleQuoted "'foo\x2018\&bar'"
 readSingleQuoted = called "single quoted string" $ do
-    id <- getNextId
+    start <- startSpan
     startPos <- getPosition
     singleQuote
     s <- many readSingleQuotedPart
@@ -1118,7 +1108,7 @@ readSingleQuoted = called "single quoted string" $ do
             when ('\n' `elem` string && not ("\n" `isPrefixOf` string)) $
                 suggestForgotClosingQuote startPos endPos "single quoted string"
 
-    endPosOfStartId id
+    id <- endSpan start
     return (T_SingleQuoted id string)
 
 readSingleQuotedLiteral = do
@@ -1554,11 +1544,11 @@ prop_readDollarBraced2 = isOk readDollarBraced "${foo/'{cow}'}"
 prop_readDollarBraced3 = isOk readDollarBraced "${foo%%$(echo cow\\})}"
 prop_readDollarBraced4 = isOk readDollarBraced "${foo#\\}}"
 readDollarBraced = called "parameter expansion" $ do
-    id <- getNextId
+    start <- startSpan
     try (string "${")
     word <- readDollarBracedWord
     char '}'
-    endPosOfStartId id
+    id <- endSpan start
     return $ T_DollarBraced id word
 
 prop_readDollarExpansion1= isOk readDollarExpansion "$(echo foo; ls\n)"
@@ -1579,13 +1569,13 @@ prop_readDollarVariable5 = isWarning (readDollarVariable >> string "[f") "$arr[f
 
 readDollarVariable :: Monad m => SCParser m Token
 readDollarVariable = do
-    id <- getNextId
+    start <- startSpan
     pos <- getPosition
 
     let singleCharred p = do
         n <- p
         value <- wrap [n]
-        endPosOfStartId id
+        id <- endSpan start
         return $ (T_DollarBraced id value)
 
     let positional = do
@@ -1599,7 +1589,7 @@ readDollarVariable = do
     let regular = do
         name <- readVariableName
         value <- wrap name
-        endPosOfStartId id
+        id <- endSpan start
         return (T_DollarBraced id value) `attempting` do
             lookAhead $ char '['
             parseNoteAt pos ErrorC 1087 "Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet)."

From b9a9eb2529e40a29224fc3114ed20d5e2c3c6d0d Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Tue, 12 Jun 2018 22:16:00 -0700
Subject: [PATCH 10/12] Change getNextId to create a zero width span at new id

---
 src/ShellCheck/Parser.hs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 8daa957..41724a5 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -185,8 +185,9 @@ getNextIdAt sourcepos = do
 
 getNextId :: Monad m => SCParser m Id
 getNextId = do
-    pos <- getPosition
-    getNextIdAt pos
+    start <- startSpan
+    id <- endSpan start
+    return id
 
 data IncompleteInterval = IncompleteInterval SourcePos
 
@@ -204,11 +205,6 @@ endSpan (IncompleteInterval start) = do
     }
     return id
 
-zeroWidthSpan = do
-    start <- startSpan
-    id <- endSpan start
-    return id
-
 addToHereDocMap id list = do
     state <- getState
     let map = hereDocMap state

From 4111ce8fde65255fe7d3f82d87ca24bbf47c0e13 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Tue, 12 Jun 2018 22:39:06 -0700
Subject: [PATCH 11/12] Make end pos non-optional

---
 src/ShellCheck/Checker.hs   |  7 ++-----
 src/ShellCheck/Interface.hs |  2 +-
 src/ShellCheck/Parser.hs    | 16 ++++++++--------
 3 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/src/ShellCheck/Checker.hs b/src/ShellCheck/Checker.hs
index 4b0ba1e..bd722ce 100644
--- a/src/ShellCheck/Checker.hs
+++ b/src/ShellCheck/Checker.hs
@@ -39,13 +39,10 @@ import Control.Monad
 import Test.QuickCheck.All
 
 tokenToPosition startMap (TokenComment id c) = fromMaybe fail $ do
-    position <- maybePosition
-    endPosition <- maybeEndPosition <|> maybePosition
-    return $ PositionedComment position endPosition c
+    span <- Map.lookup id startMap
+    return $ PositionedComment (fst span) (snd span) c
   where
     fail = error "Internal shellcheck error: id doesn't exist. Please report!"
-    maybePosition = fmap fst $ Map.lookup id startMap
-    maybeEndPosition = join $ fmap snd $ Map.lookup id startMap
 
 checkScript :: Monad m => SystemInterface m -> CheckSpec -> m CheckResult
 checkScript sys spec = do
diff --git a/src/ShellCheck/Interface.hs b/src/ShellCheck/Interface.hs
index fb5f492..9936653 100644
--- a/src/ShellCheck/Interface.hs
+++ b/src/ShellCheck/Interface.hs
@@ -61,7 +61,7 @@ data ParseSpec = ParseSpec {
 
 data ParseResult = ParseResult {
     prComments :: [PositionedComment],
-    prTokenPositions :: Map.Map Id (Position, Maybe Position),
+    prTokenPositions :: Map.Map Id (Position, Position),
     prRoot :: Maybe Token
 } deriving (Show, Eq)
 
diff --git a/src/ShellCheck/Parser.hs b/src/ShellCheck/Parser.hs
index 41724a5..2d8168f 100644
--- a/src/ShellCheck/Parser.hs
+++ b/src/ShellCheck/Parser.hs
@@ -151,7 +151,7 @@ data HereDocContext =
 
 data UserState = UserState {
     lastId :: Id,
-    positionMap :: Map.Map Id (SourcePos, Maybe SourcePos),
+    positionMap :: Map.Map Id (SourcePos, SourcePos),
     parseNotes :: [ParseNote],
     hereDocMap :: Map.Map Id [Token],
     pendingHereDocs :: [HereDocContext]
@@ -175,7 +175,7 @@ getLastId = lastId <$> getState
 getNextIdAt sourcepos = do
     state <- getState
     let newId = incId (lastId state)
-    let newMap = Map.insert newId (sourcepos, Just sourcepos) (positionMap state)
+    let newMap = Map.insert newId (sourcepos, sourcepos) (positionMap state)
     putState $ state {
         lastId = newId,
         positionMap = newMap
@@ -197,7 +197,7 @@ endSpan (IncompleteInterval start) = do
     id <- getNextIdAt start
     endPos <- getPosition
     state <- getState
-    let setEndPos (start, _) = Just (start, Just endPos)
+    let setEndPos (start, _) = Just (start, endPos)
     let newMap = Map.update setEndPos id (positionMap state)
     putState $ state {
         lastId = id,
@@ -335,9 +335,9 @@ parseProblemAt pos = parseProblemAtWithEnd pos pos
 parseProblemAtId :: Monad m => Id -> Severity -> Integer -> String -> SCParser m ()
 parseProblemAtId id level code msg = do
     map <- getMap
-    let (pos, _) = Map.findWithDefault
+    let (start, end) = Map.findWithDefault
                 (error "Internal error (no position for id). Please report.") id map
-    parseProblemAt pos level code msg
+    parseProblemAtWithEnd start end level code msg
 
 -- Store non-parse problems inside
 
@@ -2936,7 +2936,7 @@ debugParseScript string =
                 posFile = "removed for clarity",
                 posLine = -1,
                 posColumn = -1
-            }, Just Position {
+            }, Position {
                 posFile = "removed for clarity",
                 posLine = -1,
                 posColumn = -1
@@ -3108,8 +3108,8 @@ posToPos sp = Position {
     posColumn = fromIntegral $ sourceColumn sp
 }
 
-startEndPosToPos :: (SourcePos, Maybe SourcePos) -> (Position, Maybe Position)
-startEndPosToPos (s, me) = (posToPos s, fmap posToPos me)
+startEndPosToPos :: (SourcePos, SourcePos) -> (Position, Position)
+startEndPosToPos (s, e) = (posToPos s, posToPos e)
 
 -- TODO: Clean up crusty old code that this is layered on top of
 parseScript :: Monad m =>

From b63483d44cc58efc9685dbd9059d17e12dbd0411 Mon Sep 17 00:00:00 2001
From: Ng Zhi An <ngzhian@gmail.com>
Date: Tue, 12 Jun 2018 22:50:02 -0700
Subject: [PATCH 12/12] Remove unused import

---
 src/ShellCheck/Checker.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/ShellCheck/Checker.hs b/src/ShellCheck/Checker.hs
index bd722ce..f70a776 100644
--- a/src/ShellCheck/Checker.hs
+++ b/src/ShellCheck/Checker.hs
@@ -29,7 +29,6 @@ import Data.Functor
 import Data.List
 import Data.Maybe
 import Data.Ord
-import Control.Applicative
 import Control.Monad.Identity
 import qualified Data.Map as Map
 import qualified System.IO